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1
Elibol, Gulcin Cankiz. "Assessment Of Novelty And Distinctive Character In Industrial Design Protection In Turkey". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613426/index.pdf.
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Novelty and distinctive character are the conditions of protection for a registered design in Turkey. This study investigates the ways in which novelty and distinctive character are interpreted and assessed by the parties actively involved in the assessment process &ndashjudges, court experts, the Turkish Patent Institute experts, attorneys and design agents. The face-to-face interviews conducted with 51 participants from the parties involved indicate that the assessment of distinctive character presents more challenges than the assessment of novelty. Not being exactly the same with a previous design is the main consideration in the assessment of novelty. The assessment of distinctive character is primarily identified with the comparison of designs&rsquo
overall impressions whereas designer&rsquo
s degree of freedom remains as the least mentioned consideration. The study suggests that being subject to protection of designs not fulfilling the conditions of protection coupled with the uncertainties in the assessment of novelty and distinctive character, which may have a negative impact on the public trust in the design registration system. The study concludes with a set of suggestions for developing an assessment guide for the design registration system in Turkey.
2
Thorell, Julia. "UTOPIA". Thesis, Konstfack, Grafisk design & illustration, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6910.
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Mitt examensarbete består av en skriftlig del och en gestaltande del. Den skriftliga delen är en DROP, med beskrivande text och bild kring arbetsprocessen av mitt examensarbete. Den gestaltande delen består av mitt examensarbete, den grafiska novellen UTOPIA.
3
Roller, Michael T. "Refining Design Prediction Through the Principles of Typicality and Novelty". University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397467011.
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Caverly, Brian. "PERPETUAL NOVELTY". VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/1237.
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Within this thesis is a mapping out of the processes, concepts, and influences, behind the sculptural practice of Brian Caverly. From Complex Adaptive Systems to the world of order of Michel Foucault to the reexamination of the Modernist movement by Yve Alain Bois and Rosalind Krauss, a rhizomatic path of connections and lines form and cross over, weaving together into a swarming mayhem of over population. Out of this chaos and order grow complex installations and constructions that are inherently bound by the system of their making, yet attempt at every turn to escape conformity.
5
Löfqvist, Lars. "Innovation and Design Processes in Small Established Companies". Licentiate thesis, University of Gävle, Ämnesavdelningen för industriell ekonomi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-6156.
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This thesis examines innovation and design processes in small established companies. There is a great interest in this area yet paradoxically the area is under-researched, since most innovation research is done on large companies. The research questions are: How do small established companies carry out their innovation and design processes? and How does the context and novelty of the process and product affect the same processes?
The thesis is built on three research papers that used the research method of multiple case studies of different small established companies. The innovation and design processes found were highly context dependent and were facilitated by committed resources, a creative climate, vision, low family involvement, delegated power and authority, and linkages to external actors such as customers and users. Both experimental cyclical and linear structured design processes were found. The choice of structure is explained by the relative product and process novelty experienced by those developing the product innovation. Linear design processes worked within a low relative novelty situation and cyclical design processes worked no matter the relative novelty. The innovation and design processes found were informal, with a low usage of formal systematic design methods, except in the case of design processes for software. The use of formal systematic methods in small companies seems not always to be efficient, because many of the problems the methods are designed to solve are not present. Customers and users were found to play a large and important role in the innovation and design processes found and gave continuous feedback during the design processes. Innovation processes were found to be intertwined, yielding synergy effects, but it was common that resources were taken from the innovation processes for acute problems that threatened the cash flow. In sum, small established companies have the natural prerequisites to take advantage of lead-user inventions and cyclical design processes. Scarce resources were found to be the main factor hindering innovation, but the examined companies practiced several approaches to increase their resources or use existing scarce resources more efficiently in their innovation and design processes. Examples of these approaches include adopting lead-user inventions and reducing formality in the innovation and design processes.
6
Soudková, Kateřina. "Koláž žije!" Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2013. http://www.nusl.cz/ntk/nusl-232391.
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The output of my studio thesis – redesign of a book called Zůstaňte s námi by Marek Šindelka, follows to the theoretical section titled Collage in contemporary Czech illustration and brings up the know-how of said issue. This fictional redesigned story book by contemporary Czech author deals with the current possibilities of the collage technique, its practical application in the field of graphic design and strives for its reconnection with modern Czech books.
7
Hernandez, Fisher Carlos. "The design process of The Legend of Wild Man Fischer /". Burnaby B.C. : Simon Fraser University, 2005. http://ir.lib.sfu.ca/handle/1892/2353.
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8
Yeboah-Akowuah, Bright. "Novel antenna designs for body-centric applications". Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/novel-antenna-designs-for-bodycentric-applications(d70af495-ff21-4bcb-b935-7ac3e8c37f58).html.
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There is an increasing need for small, conformal and multifunctional antennas that can satisfy all sorts of communication needs and varieties of portable devices and sensors for monitoring and information gathering. One area that has received much attention in recent years include antennas for body-centric applications that can be integrated into body-worn and implantable medical devices (IMDs). Continuous reduction in size for body-worn and IMDs require ultra-small antennas for embedded applications. However, the designers of body-centric antennas are faced with numerous challenges in dealing with issues related to miniaturisation, biocompatibility, patient safety, detuning and additional challenges imposed by the human body, which significantly affects the performance of the antennas. In order to have efficient wireless communication systems, it is important to understand and characterise the effects of the human body on antenna elements, the radio propagation channel parameters and the overall system performance. The thesis is focused on design and development of antennas for body-centric applications, which involve on-body, off-body and implantable devices. Numerical simulations of the proposed antennas on human tissue-mimicking materials (phantom) were performed to determine how the human tissues affect the antenna performance. A series of measurements have been made on human body phantom made in the laboratory as well as real on-body human subject applications. Based on the numerical and statistical data obtained from these studies various antenna designs have been proposed for body-centric applications including applications in implantable devices in the Medical Implant and Communication Service band (MICS) 402-405 MHz, on-body applications in the Industrial, Scientific and Medical (ISM) band at 2.45 GHz and Ultra-wideband (UWB) spectrum 3.1 GHz - 10.6 GHz for on-body and microwave imaging applications.
9
Lakew, Nathan. "Being-human in the world of digital artifacts: holistic rethinking of design practices". Doctoral thesis, Mittuniversitetet, Avdelningen för informations- och kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-29323.
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This thesis conducts a philosophical, theoretical, and practical exploration of digital technology design to examine how digital technologies can fulfill our two-facet of existentiality – identified in the thesis as belonginess and novelty. By belonginess, I identify human’s innate need for a feeling of connectedness and harmony with the self, others, and the natural world. The word novelty implies the human interest in exploration, invention, and desire for new experiences. This research suggests that contemporary digital technologies are largely novelty need-oriented, while our belonginess need is either ignored or its growth curtailed. The research question presented in this thesis is how and why can design enable digital technologies to mediate aligned existentiality? With this broad question, I will argue that an alignment between digital technologies and our two-facet of existentiality can be met through refocused design practices. Strong arguments have been forwarded that novelty focused digital technologies can reduce our existential needs of belonginess. Digital technologies are leading consumerist commodities associated with creating unrelenting demand for new experiences. The search for constant stimulation and novelty has resulted in a fragmented and alienated state of being-human where the only way of feeling a sense of belonging comes from consuming more novel experiences. As contemporary everyday life is increasingly intertwined with digital technologies, their effect on our way of being-human becomes even more notable. Against this background, the research attempts to ‘bring back’ our needs of belonginess to an equal footing with novelty in digital technologies. I have examined the current digital technology design’s philosophical, theoretical, and practical foundations to refocus design, from its too strong focus on developing novelty experiences to mediating aligned existentiality. With the aim of refocusing the design role, a theoretical framework based on holism has emerged that could provide design a background to focus on mediating aligned existentiality. Primarily ivinformed by three thinkers – Marin Heidegger, Karl Marx, and John Dewey – the proposed holistic theoretical framework aims to provide design with a basis to (1) embed belonginess values in digital technologies (2) redirect digital technologies from alienating values such as consumerism, and (3) provide a mediating materiality for digital technologies to advance aligned existentiality while in use. The thesis further illustrates the proposed holistic dimensions – philosophy, theory, and practice – using three empirical materials. I argue that the proposed holistic foundation for design is also aligned with how digital technologies are being used in the everyday lifeworld. Consequently, by freeing design from its traditional responsibility of making technically savvy and novel artifacts and refocusing its role to mediating aligned existentiality, design can itself be used to support our being-human in the world of digital artifacts.Vid tidpunkten för disputationen var följande delarbeten opublicerade: delarbete 8 accepterat, delarbete 9 under granskning.
At the time of the doctoral defence the following papers were unpublished: paper 8 accepted, paper 9 under review.
10
DeHoog, Edward Allen. "Novel Fundus Camera Design". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195633.
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A fundus camera a complex optical system that makes use of the principle of reflex free indirect ophthalmoscopy to image the retina. Despite being in existence as early as 1900's, little has changed in the design of a fundus camera and there is minimal information about the design principles utilized. Parameters and specifications involved in the design of fundus camera are determined and their affect on system performance are discussed. Fundus cameras incorporating different design methods are modeled and a performance evaluation based on design parameters is used to determine the effectiveness of each design strategy. By determining the design principles involved in the fundus camera, new cameras can be designed to include specific imaging modalities such as optical coherence tomography, imaging spectroscopy and imaging polarimetry to gather additional information about properties and structure of the retina. Design principles utilized to incorporate such modalities into fundus camera systems are discussed. Design, implementation and testing of a snapshot polarimeter fundus camera are demonstrated.
11
Zarewych, Lara Daniv 1972. "Managing novelty at the interfaces between concept and product : case studies for the automotive industry". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34812.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2005.Includes bibliographical references (p. 86-88).
Appearance of the product is a discerning factor for the consumers purchase decisions. Time from concept to product creation is a critical factor in the competitive automotive industry. The period to develop a product is dependant on the people, content and the technology changes that constitute a large majority of expense allocation, and time invested. The greater the degree of change from something established and successful, the more difficult it becomes to incorporate the change into a product. Being successive in the automotive industry relies on the ability to maintain market presence with new and innovative products, while shortening the cycle time associated with new product design, development, and its introduction. Increasing capability to manage changes becomes more challenging as product complexity and customer demands increase and product life cycles decrease. How automotive manufacturers manage these changes during the critical product definition phase through process, tools and methods is the central discussion of this paper. The intent of this thesis is to identify the processes and key enablers that allow a rapid development process for appearance related systems, in particular the interior environment of the vehicle. Five cases that effect the interior trim environment will be reviewed to understand the methods, which allow the migration of novelty. Situations that will be studied will be introductions to aspects of: new technology, strategies, and the impact of late additions. To compare and contrast the degree of change occurring in these cases, a framework is essential to identify novelty. The ability and skills which an organization can perform changes is defined as organizational capability. This term
(cont.) describes how people within the organization manage to perform work. Specific case studies will be analyzed--reviewing the novelty introduced to the program, the organizational capability utilized, and the artifacts and processes employed to develop a final product within the division of the Sport Utility Vehicle Body on Frame, of Ford Motor Company, and contrasting comparisons to similar areas within Nissan Corporation, and Toyota Motor Corporation. Through these cases different types of novelty are revealed and its impact upon the interior trim system. It is argued that allotting more time in the preparation and early planning stages will reconcile problems that may arise later on. The approaches that these departments use: formal, informal meetings, conference calls, and written communication to manage novelty will be reviewed and compared in order to provide recommendations for improvement.
by Lara Daniv Zarewych.
S.M.
12
Zhu, Jiebei. "Novel controller designs for VSC-HVDC networks". Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=22666.
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Future power system will incorporate much higher penetrations of renewable energy than is presently the case. In particular, large offshore wind energy resources, connected to AC power systems via HVDC and VSC converters, are expected to proliferate. This thesis introduces research in the area of control of multi-terminal HVDC systems, presenting a review of the state of the art and challenges associated with respect to VSC control solutions for HVDC transmission systems. To address one of the identified challenges (effective control of a multi-terminal HVDC system), a direct current matching control strategy is developed and demonstrated. This uses telecommunications to match the input and output powers of the various VSCs. The operation of the scheme is demonstrated through several case studies, and the advantages of the strategy compared to more traditional and other proposed schemes are presented. Another major challenge associated with future power systems is a reduction in s ystem inertia, due to increased levels of energy being provided from renewable sources, which typically provide little or no inertia to the system. Voltage source converters (VSC), used in high voltage direct current (HVDC) transmission applications, are often deliberately controlled in order to de-couple the interconnected systems to prevent propagation of transients and potential for instability between the systems on either side of the VSC interface. However, this can inhibit the provision of much needed support during transients that would otherwise be available from system inertia provided by rotating plant connected to an interconnected system. Accordingly, a novel VSC-HVDC control system, termed "INEC" (INertia Emulation Control) is proposed, which enables a VSC-HVDC system to provide support that emulates the inertia of synchronous generators (SG). The energy to provide the inertial response is sourced from the capacitance of the HVDC connection, which may be augmented by the installation of additional capacitance. The proposed INEC system allows a VSC-HVDC system with a fixed capacitance to emulate a wide range of inertia constants (H) by specifying the amount of permissible DC voltage variation. The scheme is demonstrated through simulations, and its performance is evaluated for transients that include faults and also changes in load.
13
Jenkins, Michael. "Novel designs for undulator based positron sources". Thesis, Lancaster University, 2015. http://eprints.lancs.ac.uk/76604/.
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Proposed high energy electron-positron linear colliders require a high ux of positrons. To achieve this a number of new positron source designs have been proposed. One of these is an undulator-based positron source, which is the baseline positron source design for the International Linear Collider. The undulator-based positron source for the International Linear Collider uses a helical undulator to produce a intense photon beam that generates positrons through the pairproduction mechanism. As a helical undulator is used the photon beam is polarised and this results in polarised positrons being produced. This thesis investigates the undulator-based positron source design and aims to optimise it for positron production at the International Linear Collider. To do this the undulator is studied in detail as there is a large scope to design a bespoke undulator for positron production. As the particle physics community is interested in having a high positron polarisation the undulatorbased positron source needs to be optimised for yield and polarisation. In order to optimise the design of the helical undulator we derive an analytical equation for the radiation produced by a helical undulator. This is done to provide some understanding of how the dierent undulator parameters aect the photon spectrum produced by a helical undulator. In addition to the analytical equation, new software is used to calculate the photon spectra produced by non-ideal undulators in order to evaluate how a realistic undulator-based positron source would function. Using suggestions proposed in this thesis we could expect to see an increase in positron yield of of 10:9% and an increase in positron polarisation from 21:93% to 41:93 %.
14
Andersson, Oscar. "ÖVERALLT PÅ JORDEN SAMTIDIGT". Thesis, Konstfack, Grafisk design & illustration, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6941.
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Ghoreishian, Idine. "The Spiro-Helical Antenna". Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/36021.
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A novel antenna made of a spiral wire wrapped into a larger helical shape is introduced. The geometry of this antenna, which is a doubly helical structure, is fully described by five independent parameters, including two radial dimensions, two pitch angles, and the number of turns. Radiation properties of this antenna are examined both theoretically and experimentally. The Numerical Electromagnetic Code (NEC-2) is used to obtain simulation results. A large number of cases with different radii, pitch angles, and number of turns are investigated. Results for far-field patterns, gain, axial ratio, and bandwidth are presented. The influence of parameters on radiation properties are examined. Several prototypes of the antenna were constructed and tested using an outdoor antenna range. Measured far-field patterns are presented over a wide range of frequencies. The measured and computed radiation patterns are in good agreement.
The results of this study indicate that the proposed antenna provides circular polarization and high gain over a wide frequency range. For example, when the number of turns is 10, a gain of 11-14 dB, a boresight axial ratio of less than 3 dB, and a half-power beamwidth of about 40 degrees are achieved over a 30% bandwidth. The side-lobe level for most cases examined is better than 10 dB below the main beam. A unique advantage of this antenna is its much smaller size compared with a conventional helical antenna made of straight wire shaped into a helix. Having about the same radiation characteristics, including gain, circular polarization, bandwidth, and side-lobe level, this new antenna occupies a volume more than 2.5 to 3 times smaller than the conventional helix. This reduction in size, which in turn may imply smaller weight and lower packaging and manufacturing costs, makes the proposed antenna very appealing to many communications and aerospace applications.
Master of Science
16
Abhay, Srinivas. "Novel Compressor Blade Design Study". University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439279520.
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Peliks, Robert Bilgor. "Novel design of a rotary valve using axiomatic design". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32348.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (p. 110).
Rotary valves have existed for millennia; and while they have developed tremendously since the first Roman valves, many of the same problems have persisted. The basic problems are caused by the coupling of functional requirements, which limits the valve's performance. Using axiomatic design (AD), two of these couplings, including the coupling of the friction-sealing FRs, are studied and resolved. Although more work can be done to improve the patent-pending designs, the concepts presented represent advancements over existing rotary valve designs. The proposed designs have been analyzed for their merits as a valve and for their potential applications, such as in automotive engines.
by Robert (Beto) Bilgor Peliks.
S.M.
18
Gilbert, Steven M. (Steven Michael) 1975. "On infrastructure for resolving novelty in product development : a view from the fast paced world of imaging and printing". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/34807.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design & Management Program, 2004.Includes bibliographical references (p. 87-88).
Change is an absolutely essential component of product development. However, some changes are too difficult to manage. It is contended that the difficult changes stem from the emergence of novelty. The significance of novelty is that it is not immediately apparent and can be overlooked. It is a common element in disruptive technology, knowledge management, and firefighting research. This work examines the effects of emergent novelty in a complex product development system. In order to do this a framework is developed to categorize potential types of novelty that are encountered. In addition, a unique perspective on the concept of organizational capability is introduced. What makes it unique is the idea that organizational capability is composed of the capacity to do work and the ability of actors to use that capacity. "Organizational infrastructure" is used to speak more concretely about organizational capability. These conceptual models are used to analyze the events of three case studies developed from actual projects in the Imaging & Printing division of Hewlett-Packard. Through the case analysis it is shown there is significant pressures to approach development as if all novelty is understood. However, by doing so almost guarantees problems late in development if latent novelty exists. It is speculated that the addition of excess capacity to the organizational infrastructure will allow for greater novelty detection. This in turn should decrease the complications from resolving issues related to the emergence of novelty.
by Steven M. Gilbert.
S.M.
19
Dekoulis, George. "Novel digital systems designs for space physics instrumentation". Thesis, Lancaster University, 2007. http://eprints.lancs.ac.uk/6765/.
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This thesis presents the development of two novel Space Plasma Physics instruments. The few costly space weather missions (SOHO, CHAMP etc.) are justified on the qualitative basis of technological capabilities, such as high-resolution magnetometry, UV, X-ray and stray light imaging power etc. Space weather can also be studied from ground. The demands for ground measurements have increased significantly over the recent years (e.g. THEMIS field-of-view is enhanced by ground instruments). Costs associated with cleanroom procedures, space qualification, launch and operation are avoided. Low-cost ground instrumentations are easier to maintain and upgrade.
20
Bethge, Jens. "Novel designs and applications of photonic crystal fibers". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16470.
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Zuerst wird die Idee einer gechirpten photonischen Kristallfaser vorgestellt. Aus einem stark vereinfachten Modell, die qualitativen Eigenschaften dieses neuen Fasertyps abgeleitet. Hier gelingt es, alle wichtigen Designparameter zu bestimmen. Die hervorragenden Leitungseigenschaften dieser Fasern werden dann in Experimenten demonstriert. Ohne jegliche Dispersionskompensation wird die Übertragung eines 25 fs Impulses in einer 1 Meter langen Faser gezeigt. Wird zusätzlich eine Dispersionskompensation verwendet, lassen sich sogar Impulse mit weniger als 20 fs Dauer übertragen. Im Anschluss daran wird eine photonische Kristallfaser untersucht, die mit einer Flüssigkeit gefüllt ist. Die hergestellte Faser ist dahingehend optimiert, einen hoch effizienten Soliton-Fission Mechanismus zu ermöglichen, der zur Erzeugung von Weißlicht genutzt wird. Diese Weißlicht-Impulse haben eine mit Soliton-Fission bisher noch nie erreichte Energie von 390 nJ. Auf Grundlage einer guten Übereinstimmung mit den experimentellen Resultaten lässt sich aus numerischen Simulationen der zugrunde liegende Effekt bestimmen. Abschließend wird über ein Experiment berichtet, das die nichtlineare Wechselwirkung zwischen zwei Impulsen verschiedener Wellenlänge ausnutzt, um einen optischen Schalter zu verwirklichen. Dieses Experiment erfordert genaueste Kontrolle der Dispersion und der Nichtlinearität in der Faser. Bei der gleichzeitigen Propagation von zwei Impulsen wird ein neuartiger Schalteffekt beobachtet. Beide Impulse haben nahezu die gleiche Gruppengeschwindigkeit, und ihre nichtlineare Wechselwirkung basierend auf Kreuz-Phasen-Modulation wird dadurch deutlich verstärkt. Hiermit wird ein voll funktionsfähiger optischer Transistor mit gutem Schaltkontrast experimentell demonstriert, der insbesondere einen schwachen Impuls einen stärkeren Impuls schalten lässt.First, the concept of a novel chirped photonic crystal fiber is introduced. The qualitative dispersion and loss properties of this new fiber are theoretically derived. The calculated results agree excellently with experimental data obtained from fabricated fiber samples. The superior guiding properties of this new photonic fiber are demonstrated in two experiments. The delivery of 25 fs pulses over a 1 meter distance is realized without any dispersion compensation. Moreover, using dispersion compensation, the delivery of even sub-20-fs pulses becomes possible. Subsequently, a photonic crystal fiber with a liquid core is investigated, work presents effective methods for the preparation and explains a scheme for successfully reducing the insertion loss. The fiber is optimized to support the highly efficient soliton-fission mechanism at unprecedented pulse energies in white-light supercontinuum generation. Because of the liquid core, the supercontinuum generation scheme can be scaled beyond the peak-power limitations of solid-core fibers. The generation of a two-octave spanning supercontinuum with 390 nJ pulse energy is demonstrated. The experimental results are compared to a numerical simulation and the underlying mechanism is identified. Finally, an experiment is presented that exploits strong nonlinear interaction of two pulses inside a photonic crystal fiber for all-optical switching. A novel effect is observed during the co-propagation of two ultrashort pulses with different wavelengths. Because of the dispersion properties in the chosen fiber, these pulses are propagating at nearly identical group velocities, which dramatically increases the nonlinear interaction via cross-phase modulation between the two pulses. Based on this interaction, a fully functional optical transistor is experimentally demonstrated with good switching contrast. In particular, the demonstrated optical transistor enables switching of a strong pulse by a much weaker pulse.
21
Thogarcheti, Sai Subramanya Varun. "NOVEL RESOURCE EFFICIENT CIRCUIT DESIGNS FOR REBOOTING COMPUTING". UKnowledge, 2017. https://uknowledge.uky.edu/ece_etds/109.
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CMOS based computing is reaching its limits. To take computation beyond Moores law (the number of transistors and hence processing power on a chip doubles every 18 months to 3 years) requires research explorations in (i) new materials, devices, and processes, (ii) new architectures and algorithms, (iii) new paradigm of logic bit representation. The focus is on fundamental new ways to compute under the umbrella of rebooting computing such as spintronics, quantum computing, adiabatic and reversible computing. Therefore, this thesis highlights explicitly Quantum computing and Adiabatic logic, two new computing paradigms that come under the umbrella of rebooting computing. Quantum computing is investigated for its promising application in high-performance computing. The first contribution of this thesis is the design of two resource-efficient designs for quantum integer division. The first design is based on non-restoring division algorithm and the second one is based on restoring division algorithm. Both the designs are compared and shown to be superior to the existing work in terms of T-count and T-depth. The proliferation of IoT devices which work on low-power also has drawn interests to the rebooting computing. Hence, the second contribution of this thesis is proving that Adiabatic Logic is a promising candidate for implementation in IoT devices. The adiabatic logic family called Symmetric Pass Gate Adiabatic Logic (SPGAL) is implemented in PRESENT-80 lightweight algorithm. Adiabatic Logic is extended to emerging transistor devices.
22
Ruggeri, Irene <1989>. "Beyond Li-ion batteries: novel concepts and designs". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amsdottorato.unibo.it/8763/1/Thesis_IR.pdf.
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Efforts are being globally spent today to boost stored energy produced by renewable sources and to encourage a sustainable electric transportation. High-energy conversion systems like batteries can satisfy these demands in an efficient way. Although Li-ion batteries (LIBs) are the best batteries on the market in terms of energy content, a drastic change is desirable to increase both energy and power performance. In this context, Li/O2 is the next generation system due to the theoretical 10-fold higher specific energy than commercial LIBs (3500 vs. 250 Wh kg-1).
The aim of this PhD thesis is the development of novel concepts and cell designs with the purpose to increase the performance of the aprotic Li and Li/O2 batteries.
Specifically, a novel design of electrolyte (i.e. solvent-in-salt “SIS” solutions, where the salt-to-solvent ratio is higher than 1), and an innovative concept of semi-solid lithium redox flow air (O2) battery (SLRFAB) technology, based on the use of a O2-saturated semi-solid catholyte, have been proposed.
23
Poli, Federico. "Design of novel redox flow batteries". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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Questo lavoro di tesi partendo da un'analisi bibliografica delle tecnologie di batterie più avanzate allo stato solido e a flusso, sottolinea le potenzialità delle batterie metallo aria in particolare Li/O2 per applicazioni stazionarie e per il veicolo elettrico.
L'ottimizzazione delle prestazioni delle batterie a flusso richiede un'accurata ingegnerizzazione del disegno di cella e studi di fluidodinamica per la valutazione dell'impatto dei flussi sul funzionamento della batteria. Le cadute di pressione attraverso la cella generano, infatti, una perdita di potenza che deve essere minimizzata mediante opportune geometrie di cella.
Lo scopo di questa tesi è la modellizzazione e la valutazione sperimentale delle cadute di pressione attraverso prototipi di laboratorio di celle Li/O2
L’analisi dei disegni di celle a flusso proposte in letteratura ha permesso di realizzare un primo prototipo ottenuto con stampa 3D cha ha evidenziato come un intelligente geometria di cella permetta di ridurre drasticamente le cadute di pressione anche con sistemi viscosi quali gli elettroliti organici utilizzati nelle batterie a più alta energia specifica.
L'integrazione tra simulazioni numeriche e prove elettrochimiche su celle Li/O2 reali ha permesso di proporre il disegno di un terzo prototipo di cella sempre con l'obbiettivo di massimizzare la potenza netta della cella.
Da sottolineare che l'accuratezza della descrizione fluidodinamica nei prototipi virtuali studiati ha avuto conferma dalle misure sperimentali effettuate.
Questa tesi pertanto contribuisce a dimostrare come gli approcci numerici utilizzati siano metodi estremamente potenti per accelerare l'attività di prototipazione di batterie redox a flusso avanzate, in particolare metallo aria, e per portare tali tecnologie a raggiungere valori di energie e potenze specifiche superiori rispetto allo stato dell'arte.
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Keller, Charles Anderson. "Novel Concepts in Piezohydraulic Pump Design". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5144.
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Over the past several years, there has been significant development in the field of applications for piezoelectric materials. This thesis focuses on using these materials in a piezohydraulic pump system. Piezopump systems typically operate by pushing fluid through check valves to produce positive fluid flow. The accompanying hydraulic system utilizes a control valve, hydraulic accumulator, and hydraulic actuator. The function of the piezopump is to convert the very small displacements of the piezoelectric stack actuators into useful work. This paper details the design, construction, and testing of four such possible pumping systems.
The first system was a thin diaphragm piezo pump which utilized conventional check valves to rectify the flow. This pump was the next generation system in a series of piezopumps designed at Georgia Tech. Its peak performance with a driving voltage of 150V was a flowrate of 140 cc/min with a blocked pressure of 1.38 MPa (200 psi.). The key features of this system were its aluminum construction and ease of assembly.
A new technology was developed which used a resonant fluid cavity to build usable pressure for a pumping system. Two half wave resonators were build to operate at frequencies of 20 kHz and 1 kHz. These systems produced good pressure during resonance, but attempts to rectify these high frequency pulses were unsuccessful. Rectification methods such as reed valves, vortex fluid diodes, and nozzle/ diffuser arrangements were discussed. A reed valve system was developed and tested. A fourth piezoelectric system was developed which used the driving elements and the reed valves originally designed for the resonant systems. This non resonant reed valve pump produced good results. This pump systems produced 338cc/min at a frequency of 400 Hz. It also produced a blocked pressure of 250 psi. There are many applications for these miniature high flow pumping systems. The technology in the reed valve pump is scalable, and the size of this particular system may be reduced dramatically to offer even more space saving potential.
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Jiang, Lin. "Novel catalysts by computational enzyme design /". Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/9248.
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Harradine, Mark Alan. "Design of a novel micro-loudspeaker". Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324442.
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Moazzam, Mohammad Reza. "Novel design techniques for microwave filters". Thesis, King's College London (University of London), 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295724.
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Hsieh, Pei-Shan. "IGBT design, modelling and novel devices". Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708993.
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Charalampidis, Nikolaos. "Novel approaches in voltage-follower design". Thesis, Oxford Brookes University, 2006. http://radar.brookes.ac.uk/radar/items/bad01df9-ee82-88aa-e5c8-2d241fb8a2fc/1.
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The aim of this research programme was to design and develop novel voltagefollowerslbuffers, suitable for radio frequency (RF) applications. The emphases throughout has been on improving key characteristics, in particular distortion, operating bandwidth, input and output impedances, offset-voltage and power supply demands of the design. The majority of the results of this work have been reported by the author in the technical literature (I] to (6). Initially this research focuses on the investigation of the underlying operating principles of the voltage-follower to provide an in-depth understanding of its operation. This study concentrates on establishing reasons for the poor distortion, low input and high output impedances and increased offset-voltage and confirmed that these designs have inherently poor performance in these parameters. The analysis is carried out using both theoretical modelling and computer simulation, using the wellestablished software package ORCAD PSpice. Despite the availability of high performance computer simulation tools, it becomes apparent that 'hand' calculations in the design process, generally based on DC and small-signal transistor parameters, are essential. Therefore a detailed analysis of the transistor-models used throughout this research is carried out with PSpice data. Using the analytical results of the conventional voltage-follower as a benchmark, various novel circuit techniques investigated. Several new circuits are proposed with respect to improving the previously mentioned key characteristics. The first technique comprises local feedback and single-valued current biasing and 111 consists of emitter-followers exclusively throughout the signal path, keeping the distortion of the input signal to low levels [1 J, (2). The second technique is based on local feedback with double-valued current biasing, increasing somewhat the power dissipation but reducing, notably, the distortion of the configuration [3J, [4J, [5J, [6J. The final technique employs the emitter-followers throughout the signal path in combination with global feedback and double-valued current biasing, which presents significantly better results, on certain parameters, than conventional and existing configurations. It is anticipated that this work will be published in the near future.
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MacQuarrie, Stephanie Lee. "Design and Synthesis of Novel Benzodiazepines". Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/30209.
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Bivalent drug design is an efficient strategy for increasing potency and selectivity of many drugs. We devised a strategy to prepare agonist-benzodiazepine heterodimers that could simultaneously bind to agonist and BZD sites of the GABAAR. We synthesized a benzodiazepine-MPEG model compound that relied on physiological GABA to elicit flux. We established that a tether at the N1 position of the BZD would not prevent binding to the receptor. However, coupling of GABA amides with long chain PEG tethers studied by another group member resulted in complete loss of agonist activity. We therefore ceased research in this particular area.
1,4-Benzodiazepin-2,5-diones display a wide range of pharmacological activities. Compounds containing the tricyclic proline-derived subtype have received attention as potent anxiolytic agents and as starting materials for anthramycin-inspired anticancer agents. More recently enantiopure (S)-proline-derived 1,4-benzodiazepin-2,5-diones have been recognized as selective α5 GABAA receptor ligands. Despite the impressive diversity of 1,4-benzodiazepine-2,5-diones prepared to date, enantiopure examples possessing a quaternary stereogenic center have been largely unexplored.
"Memory of chirality" (MOC) is an emerging strategy for asymmetric synthesis. This technique enables the memory of a sole chiral center in the substrate to be retained in a process that destroys that center. We have used this technique to prepare a library of quaternary proline-derived, thioproline-derived and hydroxyproline-derived 1,4-benzodiazepin-2,5-diones, in high ee. We have developed an efficient synthetic method for preparing oxaproline-derived 1,4-benzodiazepin-2,5-diones in high yields, and by applying the MOC strategy we have prepared quaternary derivatives in acceptable %ee. We envision oxaproline-derived 1,4-benzodiazepin-2,5-diones may exhibit similar or more potent pharmacological properties than proline-derived 1,4-benzodiazepin-2,5-diones. Using density functional theory (DFT) methods, we modeled the formation of an enantiopure, dynamically chiral enolate intermediate and the slow racemization of the enolate on the alkylation reaction time scale.Ph. D.
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Hill, Marcus Peter. "Design of novel tobramycin loaded therapeutics". Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.706976.
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Ng, Lik Yin. "Novel integrated design techniques for biorefineries". Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/29016/.
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Utilisation of biomass is identified as one of the promising solutions to reduce society’s dependence on fossil fuels and mitigate climate change caused by the exploitation of fossil fuels. By using the concept of biorefinery, biomass can be converted into value-added products such as biofuels, biochemical products and biomaterials in a greener and sustainable way. To enhance the efficiency of biorefinery, the concept of integrated biorefinery which focuses on the integration of various biomass conversion technologies is utilised. To date, various biomass conversion pathways are available to convert biomass into a wide range of products. Due to the substantial amount of potential products and conversion technologies, determining of chemical products and processing routes in an integrated biorefinery have become more challenging. Hence, there is a need for a methodology capable of evaluating the integrated process in order to identify the optimal products as well as the optimal conversion pathways that produce the identified products. This thesis presents a novel approach which integrates process with product design techniques for integrated biorefineries. In the proposed approach, integration between synthesis of integrated biorefinery and computer-aided molecular design (CAMD) techniques is presented. By using CAMD techniques, optimal chemical product in terms of target properties which fulfils the required product needs is designed. On the other hand, in order to identify the conversion pathways that produce the identified optimal chemical product in an integrated biorefinery, chemical reaction pathway map (CRPM) and superstructural mathematical optimisation approach have been utilised. Furthermore, this thesis also presents various chemical product design approaches. In order to solve chemical design problems where multiple product needs are required to be considered and optimised, a novel multi-objective optimisation approach for chemical product design has been presented. By using fuzzy optimisation approach, the developed multi-objective optimisation approach identifies optimal chemical product based on multiple product properties. In addition, fuzzy optimisation approach has been further extended to address chemical product design problems where the accuracy of property prediction model is taken into account. A robust chemical product design approach is developed to design optimal chemical products with consideration of accuracy of property prediction model. Furthermore, together with CAMD techniques and superstructural mathematical optimisation approach, the developed multi-objective optimisation approach has been utilised for the design of mixtures in an integrated biorefinery. For this purpose, a systematic optimisation approach has been developed to identify optimal mixture based on multiple desired product needs as well as the optimal conversion pathways that convert biomass into the optimal mixture. Finally, possible extensions and future opportunities for the realm of the research work have been highlighted in the later part of this thesis.
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Lerner, Scott Allen. "Optical design using novel aspheric surfaces". Diss., The University of Arizona, 2000. http://hdl.handle.net/10150/289160.
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Advancements in the design, manufacturing and testing of optical systems have created the need for new functional representations for aspheric surfaces. The representations must define surfaces that can compensate for a high degree of wavefront asphericity and represent steeply sloped surfaces as the surface normal becomes perpendicular to the optical axis. As the standard asphere is explicitly defined, the range of surfaces that it can properly describe is limited. This work develops both a parametrically defined surface approach and an implicitly defined surface approach. Whereas the surface sag of an explicit surface is defined directly using one equation, the sag of a parametric surface is defined using at least two equations. The sag of an implicit surface is defined indirectly using a surface function. The utility of these novel approaches is demonstrated using examples of current interest. Specifically, a truncated parametric Taylor surface and an implicit xyz-polynomial surface are shown to be more general definitions that represent highly aspheric surfaces better the standard explicit asphere. Ray tracing and optimization strategies for parametric and implicit surface representations are discussed. Additionally, this work shows that a Fourier series is not a useful optical surface and introduces the explicit superconic surface, which is a redefinition of the standard superconic surface. Finally, we compare the surface types discussed for ray tracing speed, optimization complexity, and ability to represent highly aspheric surfaces.
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Wood, Virginia Ann. "Design and synthesis of novel antioxidants". Thesis, University of Bath, 1999. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301963.
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Yun, Gang. "Novel designs and theories for holographic fiber networking components". Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6780.
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The author's major contributions presented in this Ph.D. thesis are three novel design techniques (or concepts) for implementation of efficient holographic fiber networking components. The first concept is termed grating degeneration, which allows sharing of one holographic grating by more than one wave pair. This makes it possible to use a single grating as a number of 2 x 2 couplers in parallel, and the number of gratings required for fiber N x N couplers can be significantly reduced. The second concept is the so-called sandwich structure. By using a sandwich structure, a multi-stage topology, instead of a complete mesh, can be incorporated in the construction of a grating system in a coupler. This again can simplify the structure of an N x N coupler, especially when combined with the grating degeneration technique. The third technique, called quasi-Bragg diffraction is introduced in this thesis for the construction of 16 x 16 couplers. It turns out that when designed properly, the number of gratings required by a 16 x 16 coupler can be reduced to two per slab. The key technique is to use off-Bragg diffraction while keeping the violation of Bragg condition much higher for the unwanted waves than for the wanted waves. This technique may also be applied to other grating-based components. More generally, all of the three presented techniques may be applied to any multiple-grating-based component. An example is given in this thesis for applying grating degeneration to the construction of 8 x 8 wavelength routing couplers. Another aspect of the author's contribution is the development of a generalized diffraction theory. The major features of the theory are the rigorousness and the generality. On one hand, the theory is rigorously based on Maxwell's equations, which makes it a realistic model for simulations and analyses. On the other hand, the theory places no restrictions on light polarization, the incident wave direction and the parameters of the grating system. This is vital to the design of a multi-grating system using grating degeneration because of the three-dimensional arrangement of the wave vectors. Jones matrices are used for a complete characterization of any grating-bearing slabs. (Abstract shortened by UMI.)
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Ford, Chris L. "Novel lean burn injector designs for improved flowfield uniformity". Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/14505.
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Currently there is unprecedented social and political pressure to minimise anthropogenic environmental change. It is a result of the paradoxical nature of emissions reduction that lean-burn technology has become the most likely agent by which future emission targets may be met. However, the inclusion of lean-burn technology requires that the flametube depth is increased, to maintain an acceptable level of pressure drop and sufficient residence time. The injector too must increase in diameter as the admission of air via the fuel nozzle is increased. Maintaining traditional dump style architecture and employing these changes creates a number of additional problems. Most notable is the increased non-uniformity which is inherited by the injector flow as a result of the mismatch between the injector and upstream feed. Injector non-uniformity is a parameter symbiotic with emissions performance and it is therefore imperative to minimise the degree of injector non-uniformity if the ambition of the lean-burn system is to be realised.
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Hart, Bryan Leonard. "Novel analogue circuit designs exploiting the principles of matching". Thesis, Oxford Brookes University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.493431.
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Lagerkvist, Love. "Neural Novelty — How Machine Learning Does Interactive Generative Literature". Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-21222.
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Every day, machine learning (ML) and artificial intelligence (AI) embeds itself further into domestic and industrial technologies. Interaction de- signers have historically struggled to engage directly with the subject, facing a shortage of appropriate methods and abstractions. There is a need to find ways though which interaction design practitioners might integrate ML into their work, in order to democratize and diversify the field. This thesis proposes a mode of inquiry that considers the inter- active qualities of what machine learning does, as opposed the tech- nical specifications of what machine learning is. A shift in focus from the technicality of ML to the artifacts it creates allows the interaction designer to situate its existing skill set, affording it to engage with ma- chine learning as a design material. A Research-through-Design pro- cess explores different methodological adaptions, evaluated through user feedback and an-in depth case analysis. An elaborated design experiment, Multiverse, examines the novel, non-anthropomorphic aesthetic qualities of generative literature. It prototypes interactions with bidirectional literature and studies how these transform the reader into a cybertextual “user-reader”. The thesis ends with a discussion on the implications of machine written literature and proposes a number of future investigations into the research space unfolded through the prototype.
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Shuchi, Sarah N. "A novel concept for airport terminal design integrating flexibility". Thesis, Queensland University of Technology, 2016. https://eprints.qut.edu.au/93011/1/Sarah_Shuchi_Thesis.pdf.
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The current research proposed a conceptual design framework for airports to obtain flexible departure layouts based on passenger activity analysis obtained from Business Process Models (BPM). BPMs available for airport terminals were used as a design tool in the current research to uncover the relationships existing between spatial layout and corresponding passenger activities. An algorithm has been developed that demonstrates the applicability of the proposed design framework by obtaining relative spatial layouts based on passenger activity analysis. The generated relative spatial layout assists architects in achieving suitable alternative layouts to meet the changing needs of an airport terminal.
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Guan, Congying. "Prototyping a novel apparel recommendation system : a feasibility study". Thesis, Northumbria University, 2017. http://nrl.northumbria.ac.uk/36289/.
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This research explores the technical feasibility of developing a knowledge-based apparel style recommendation system through investigations on apparel communication theory, data construction and machine learning techniques. It intends to improve the poor user experiences of online clothes shopping caused by the unpractical style searching, recommendation and personal styling engines. This study started with building up the theoretical foundation of apparel data and recommendation system. Then, an apparel data coding method and two apparel datasets are developed based on the apparel communication system and semiotics theory. ATTRIBUTE dataset captures natural and design features while MEANING dataset labels communicative meanings on style and body. Thirdly, the technical feasibility is investigated by statistics analytical methods to evaluate data relations and machine-learning methods to learn from the training data and predict apparel MEANINGs. The author found that the proposed data might exist non-linear relations, which restricts statistics analytical methods. Instead, machine-learning based methods are applicable as evidenced by three apparel MEANING prediction models. The three models also prove that the new apparel data coding method and ATTRIBUTE dataset could enhance the learning model since it captures more accurate apparel features. Additionally, the most useful data learning method is identified when it firstly learns ATTRIBUTEs from images via CNN model, and then determines MEANINGs from predicted ATTRIBUTEs by LKF classifier. The conclusion from this research is that it is technically feasible to develop an apparel style recommendation system. This research contributes a new method to the field of apparel recommendation system study. It fills the gap of lacking deep understandings of apparel knowledge. The proposed approach made three improvements: (1) a profound theory of apparel as a foundation, (2) a new apparel dataset construction method capturing design features and connotative meanings, and (3) the image-attribute collaborated data training model, which can effectively recognise in-depth design features and make precise predictions on connotative meanings.
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Loton, Neil. "Novel routes to designer silicas". Thesis, Brunel University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385136.
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Musik, Joanna. "Substrate Specificity of Signal Peptidase, LepB, as an Adjunct to Design of Novel Inhibitors". Thesis, Griffith University, 2022. http://hdl.handle.net/10072/419079.
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Bacterial secreted proteins require an N-terminal signal peptide to leave the cytoplasm. Once the protein has been translocated across the cytoplasmic membrane, the signal peptide is cleaved by a signal peptidase (SPase), allowing the remainder of the protein to fold into its mature state. SPase I found in prokaryotes (P-type) and eukaryotes (ER-type) have the same function, but are structurally different, which makes bacterial SPase I an attractive antibiotic target. The major difference between the P-type and ER-type SPases is the catalytic dyad present in the active site, with prokaryotes utilising a Ser-Lys dyad, while eukaryotes utilise a Ser-His dyad. SPase I of E. coli, LepB, removes the signal peptide from non-lipoproteins and cleaves after the canonical sequence Ala-X-Ala. Amino acids surrounding the SPase I cleavage site have been shown to affect the efficiency of protein secretion. The amino acids before the cleavage site (P1 onwards) have been well studied. However, the amino acids after the cleavage site, in the mature protein region (P1′ onwards), have not been not been studied thoroughly and are the focus of my PhD studies.
We first investigated a bias against aromatic amino acids at the second position after the cleavage site (P2′) in E. coli secreted proteins. Maltose binding protein (MBP) was mutated to introduce aromatic amino acids (tryptophan, tyrosine and phenylalanine) at P2′. All mutants with aromatic amino acids at P2′ were exported less efficiently, indicated by an increase in precursor protein. The binding kinetics of peptides that encompass the MBP cleavage site to LepB also showed a slower off-rate compared to MBP wild-type peptide.
A study of secreted proteins to look for aromatic amino acid at P2′, revealed the Bacillus subtilis protein TasA, which contains a phenylalanine at P2′. B. subtilis has five type I signal peptidases, one of these, SipW, is an ER-type peptidase. SipW is expressed in an operon (tapA-sipW-tasA) and is responsible for removing the signal peptide from two proteins: TapA and TasA. It is unclear from the signal peptide sequence of TasA and TapA, why an ER-type signal peptidase is required for their processing. Bioinformatic analysis of TasA and TapA indicates that both contain highly similar signal peptide cleavage sites, both predicted to be cleaved by LepB. Expressing full length TasA in E. coli is toxic and leads to cell death. To determine if this phenotype is due to the inability of the E. coli LepB to process the TasA signal peptide, we fused the TasA signal peptide and two amino acids of mature TasA (up to P2′) to both maltose binding protein (MBP) and β- lactamase (Bla); both model systems of E. coli secretion. We observed a defect in secretion, indicated by accumulation of unprocessed protein with both TasA-MBP and TasA-Bla fusions. A series of point mutations in both TasA-MBP and TasA-Bla were made around the junction of the TasA signal peptide and the fusion protein. Both of these studies indicate that residues around II the predicted TasA signal sequence cleavage site, particularly the sequence from P3 to P2′, inhibit processing by LepB.
To determine why the TasA sequence was inhibitory in E. coli, we designed 11 peptides to mimic the inefficiently cleaved secreted proteins, wild-type TasA and the TasA-MBP fusion. These peptides were studied to determine whether the peptides interact with and inhibit the function of LepB. The binding affinity and inhibitory potential of the peptides against LepB was assessed by surface plasmon resonance (SPR) and a LepB enzyme activity assay. Molecular modelling of the interaction between TasA-MBP and LepB indicated that the tryptophan residue at P2 (two amino acids before the cleavage site) inhibited the active site serine-90 residue on LepB from accessing the cleavage site. Substituting the P2 tryptophan with alanine (W26A) allowed for more efficient processing of the signal peptide when TasA-MBP was expressed in E. coli.
In this study we determined that aromatic amino acids at P2′ of secreted proteins leads to a slower release from SPase I. In addition, we uncovered the potential of the TasA signal peptide and early mature region to be used as an inhibitor for P-type SPases as it is cleaved by the ER-type SPase SipW, but inefficiently cleaved by the P-type SPase LepB.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Institute for Glycomics
Full Text
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Lalwani, Sanjiv Kumar Shankerdass. "Design and synthesis of novel isoelectric buffers". Texas A&M University, 2004. http://hdl.handle.net/1969.1/3356.
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Hydrolytically stable, low- and high-pI isoelectric hydrogel membranes were
prepared from poly(vinyl alcohol) (PVA) as alternatives to polyacrylamide-based
isoelectric membranes that hydrolyze in acidic and basic solutions.
Low-pI membranes were made by attaching an isoelectric buffer of a welldefined
pI value (such as iminodiacetic acid, IDA, aspartic acid, ASP or glutamic acid,
GLU) to the PVA backbone and crosslinking the PVA strands, in situ. The pH in these
membranes does not change significantly with slight variations in the amount of
isoelectric buffer that gets incorporated. The pI values of these membranes were pI is greater then 1.7 but less then 2.0 (IDAPVA), pI is greater then 2.0 but less then 2.6 (ASPPVA) and pI was greater then 2.6 but less then 3.4 (GLUPVA).The membranes were used as anodic membranes in isoelectric trapping (IET) experiments. Sugars, cyclodextrins (CDs), and certain polyhydroxy compounds have pKa
values between 11.5 and 14. Thus, high-pI hydrogels were obtained by incorporating (i)
quaternary ammonium derivatives of Beta-CD (QCDPVA) (ii) quaternary ammonium groups and Beta-CD (CDQPVA) and (iii) quaternary ammonium groups alone (QPVA) into the crosslinked PVA hydrogels. All three membranes had pI values greater than 11 and
served as effective cathodic membranes for the IET of small ampholytic molecules and
proteins. In pH-biased IET, proteins are collected into solutions of isoelectric buffers that set the pH to keep the proteins in a charged state affording high solubility and preventing precipitation. Thus, a series of isoelectric buffers (biasers) with high buffering capacity, high conductivity, and pI values covering the useful pH 2-10 range are needed.
Two sets of such buffers were designed (i) with pI values between the pKa values of two carboxylic acid groups and (ii) with pI values between the pKa values of the conjugate acid form of two amine groups. Six of these buffers were synthesized and their synthesis was optimized. The products were obtained in their pure, isoelectric form and were extensively characterized.
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Li, Jianzhou, i University of Lethbridge Faculty of Arts and Science. "Design of a novel hybrid cryptographic processor". Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/266.
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A new multiplier that supports fields GF(p) and GF (2n) for the public-key cryptography, and fields GF (28) for the secret-key cryptography is proposed in this thesis. Based on the core multiplier and other extracted common operations, a novel hybrid crypto-processor is built which processes both public-key and secret-key cryptosystems. The corresponding instruction set is also presented. Three cryptographic algorithms: the Elliptic Curve Cryptography (ECC), AES and RC5 are focused to run in the processor. To compute scalar multiplication kP efficiently, a blend of efficient algorthms on elliptic curves and coordinates selections and of hardware architecture that supports arithmetic operations on finite fields is requried. The Nonadjacent Form (NAF) of k is used in Jacobian projective coordinates over GF(p); Montgomery scalar multiplication is utilized in projective coordinates over GF(2n). The dual-field multiplier is used to support multiplications over GF(p) and GF(2n) according to multiple-precision Montgomery multiplications algorithms. The design ideas of AES and RC5 are also described. The proposed hybrid crypto-processor increases the flexibility of security schemes and reduces the total cost of cryptosystems.viii, 87 leaves : ill. (some col.) ; 28 cm.
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Tiwari, Laxmikant. "Design and synthesis of novel anion receptors". Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312677.
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Khristova, Tetiana. "Computer-aided design of novel antithrombotic agents". Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01018545.
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Thrombosis is the most important pathological process underlying many cardiovascular diseases, which are responsible for high mortality worldwide. In this theses the computer-aided design of new anti-thrombotic agents able to inhibit two types of receptors located on the surface of the platelets has been applied. The first one - αIIbβ3 - is responsible for the interaction of activated platelets with fibrinogen to form clots, whereas the second one - thromboxane A2 - is responsible for platelet activation by one of agonists excreted by activated platelets. To achieve this, different types of models have been developed using experimentally available information and structure of protein-ligand complexes. This concerns: QSAR models, structure-based and ligand-based 3D pharmacophore models, 2D pharmacophore models, shape-based and molecular field-based models. The ensemble of the developed models were used in virtual screening. This study resulted in suggestion of new potential antagonists of αIIbβ3 and thromboxane A2 receptors. Suggested antagonists of αIIbβ3 able to bind either open or closed form of the receptor have been synthesized and tested experimentally. Experiments show that they display high activity; moreover some of theoretically designed compounds are more efficient than Tirofiban - the commercialized drug molecule. The recommended antagonists of thromboxane A2 receptor have been already synthesized but biological tests have not been completed yet.
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Darling, Maureen. "The design of novel glass-ionomer cements". Thesis, University of Greenwich, 1993. http://gala.gre.ac.uk/6142/.
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Guo, Yunchuan. "Analysis and design of novel electromagnetic metamaterials". Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/7864.
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This thesis introduces efficient numerical techniques for the analysis of novel electromagnetic metamaterials. The modelling is based on a Method of Moments modal analysis in conjunction with an interpolation scheme, which significantly accelerates the computations. Triangular basis functions are used that allow for modelling of arbitrary shaped metallic elements. Unlike the conventional methods, impedance interpolation is applied to derive the dispersion characteristics of planar periodic structures. With these techniques, the plane wave and the surface wave responses of fractal structures have been studied by means of transmission coefficients and dispersion diagrams. The multiband properties and the compactness of the proposed structures are presented. Based on this method, novel planar left-handed metamaterials are also proposed. Verifications of the left-handedness are presented by means of full wave simulation of finite planar arrays using commercial software and lab measurement. The structures are simple, readily scalable to higher frequencies and compatible with low-cost fabrication techniques.
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MacSween, Ross. "Design and synthesis of novel host systems". Thesis, University of Glasgow, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443390.
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McArthur, Duncan Robert. "Design and synthesis of novel sila-peptidomimetics". Thesis, University of Glasgow, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250791.
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